CEC (Consumer Electronics Control)

Luke · ‎04.01.2022

CEC (Consumer Electronics Control)

Definition

Consumer Electronics Control (CEC) provides cross-component control functions such as One Touch Play/Record, System Standby, Preset Transfer, etc. for electronic entertainment devices. The CEC interface is derived from AV-Link, which has been the predominant control standard in Europe to date.

Ideally, this allows a maximum of 15 devices (e.g. TV, radio, CD player, amplifier, etc.) to be controlled together across manufacturers, provided that all networked devices support CEC. An essential design basis is the TV set as the destination of all signals and the remote control of the TV set as the control of the entire system. Due to this one-screen approach, problems inevitably arise with HDMI distributors and in multi-room systems because there are naturally several destinations, but this is not provided for with CEC when addressing it. Apart from the general abandonment of CEC, this problem can only be solved by systems that allow the isolation or routing of CEC traffic independently of audio and video signals.

CEC uses a simple serial, single-wire data bus, such as is optionally available with HDMI connections (on <pin 13). The nominal data bit duration is approx. 2.4 ms, which corresponds to a data rate of approx. 417 bit/s. The connection is established and the CEC capability is checked in the course of the EDID handshake during the hot-plug event. This takes place when the units are switched on or when an HDMI plug is inserted into an HDMI socket.